What is that noise?" is the usual question asked by those hostile to experimental sound when confronted with a fine session like this. The follow up is often a demand to explain how this seemingly random collection of scrapes, scratches and reverberations could even be thought of as music.

The answer, as Louis Armstrong was once reported to reply when asked for a definition of jazz, is: "If you don't know what it is, don't mess with it."

Simplistic perhaps, but applying one set of standards to a different style of expression is as fallacious as condemning a dog for not having cow horns. Both creatures are domesticated, have a tail, walk on four legs, don't talk and are reasonably loyal and friendly. But no one expects Rover to resemble Elsie, so why should pure improv approximate conventional popular sounds?

Just because isn't good enough. Since sound explorers like the American Maroney and German Tammen have decided to devote their careers to inserting objects under a piano's strung frame or radically detuning and reverse-engineering an electric guitar, they should really be celebrated for the new tones they create.

Someone once theorized that the history of Western music over the past couple of centuries has been the gradual acceptance of what once was thought of as "noise" as conventional music. BILLABONG may seem "far out" today, but will it still be so in 2050? After all, some of the eclectronica practiced by Tammen isn't so far from what you'll hear, bloated with a heavier rhythmic thud, blasting from the speakers at a dance hall rave. Plus any loudness here can certainly never compare to the wall of sound produced by a heavy metal band at full-throttle.

That too isn't exactly the point either. On the contrary, clear-eared listeners of this session will revel in the multiplicity of sounds, tones and even "noises" coming from these traditional instruments — and note how they're mixed and matched. On "Bilge", for instance, what could be a 1960s guitar rave up is played off against something resembling harpsichord crunches, while the futuristic spaceship beeps on "Bog" have to coexist with what could be harp string glisses from the piano. Heck, about half way through "Bounce" you can even hum along to a pretty conventional "bouncy" melody.

Billabong is an Australian expression for a blind channel leading out from a river. Brave souls unafraid of adventure or "noise" will follow this BILLABONG into the uncharted waters to see what adventure results.